window.onload = function () {
    document.getElementById("catalogue_first").classList.add("active");
    document.getElementById("zone_first").classList.add("active_a");
}

function select(url) {
    var id = document.getElementById(url.id);
    var zone = document.getElementsByClassName("zone1");
    var zone_a = document.getElementsByClassName("zone");

    for (var i = 0; i < zone.length; i++) {
        var catalogue = document.getElementById("catalogue"+(i+1));
        if (id === zone[i]) {
            zone[i].classList.add("active");
            zone_a[i].classList.add("active_a");
            catalogue.style.display = "block";
        }else {
            zone[i].classList.remove("active");
            zone_a[i].classList.remove("active_a");
            catalogue.style.display = "none";
        }
    }
}
function page() {
    window.top.location.href = "../IndexServlet";
}